track JuliaLang change for names -> fieldnames

ref: JuliaLang/julia#10325

src/ProtoBuf.jl

@@ -20,6 +20,7 @@ end
 if isless(Base.VERSION, v"0.4.0-")
 import Base.rsplit
 rsplit{T<:String}(str::T, splitter; limit::Integer=0, keep::Bool=true) = rsplit(str, splitter, limit, keep)
+fieldnames(t) = names(t)
 end
 
 if isless(Base.VERSION, v"0.4.0-")
@@ -44,7 +45,7 @@ function copy!(to::Any, from::Any)
     fromtype = typeof(from)
     (totype != fromtype) && error("Can't copy a type $fromtype to $totype")
     fillunset(to)
-    for name in totype.names
+    for name in fieldnames(totype)
         if isfilled(from, name)
             setfield!(to, name, getfield(from, name))
             fillset(to, name)

src/codec.jl

@@ -369,7 +369,7 @@ function meta(typ::Type, required::Array{Symbol,1}, numbers::Array{Int,1}, defau
     cache ? (_metacache[typ] = m) : m
 
     attribs = ProtoMetaAttribs[]
-    names = typ.names
+    names = fieldnames(typ)
     types = typ.types
     for fldidx in 1:length(names)
         fldtyp = types[fldidx]
@@ -409,7 +409,7 @@ function filled(obj)
     haskey(_fillcache, oid) && return _fillcache[oid]
 
     fill = Symbol[]
-    for fldname in names(typeof(obj))
+    for fldname in fieldnames(typeof(obj))
         isdefined(obj, fldname) && push!(fill, fldname)
     end
     if !isimmutable(obj)
@@ -443,7 +443,7 @@ end
 abstract ProtoEnum
 
 function lookup(en::ProtoEnum, val::Integer)
-    for name in typeof(en).names
+    for name in fieldnames(typeof(en))
         (val == getfield(en, name)) && return name
     end
     error("Enum $(typeof(en)) has no value: $val")